Turret indexing mechanism



INVENTOR.

om'Ynnn April 29, 1969 HIROFUMI TOMIYAMA TURRET INDEXING MECHANISM FiledAug. 1, 1967 FIG-,2

April 1969 HIROFUMI TOMIYAMA 3,440,905

TURRET INDEX ING MECHANI SM Filed Aug. 1. 1967 Sheet of a 1 NV ENTOR:

United States Patent 3,440,905 TURRET INDEXIN G MECHANISM HirofumiTomiyama, 1000 Akiwa, Ueda-shi, Nagano-ken, Japan Filed Aug. 1, 1967,Ser. No. 657,633 Int. Cl. F1611 27/10 US. Cl. 74822 4 Claims ABSTRACT OFTHE DISCLOSURE In a turret indexing mechanism including a turret, anindex gear and a rotating ring having a plurality of equally spacedcircumferential depressions which are rotatably mounted on a saddle,there are provided a first fluid pressure (hydraulic) cylinder pivotallyconnected to the saddle and adapted to drive a rack, a second fluidpressure cylinder adapted to operate a dowel pin to engage and disengagea selected one of said depressions and a motion transmitting linkageresponsive to the operation of the second fluid pressure cylinder topivot the first fluid pressure cylinder, thus establishing orinterrupting driving connection between the index gear and the rack.

This invention relates to an indexing mechanism for a turret carryingworking tools.

One object of this invention is to provide an improved turret indexingmechanism which has simple and rugged construction and can accuratelyposition the turret to the desired indexing position without beingaffected by excessive rotation of the turret due to inertia of rotationthereof (such excessive rotation being aggravated by the unbalance amongthe weights of tools mounted on respective positions of the turret).

Another object of this invention is to eliminate undesirable effectscaused by shocks which are generated when the turret engages with meansadapted to prevent excessive rotation thereof.

According to this invention these and other objects can be attained byproviding a turret indexing mechanism comprising a turret, an indexgear, a rotating ring having a plurality of equally spaced depression onthe periphery thereof, a saddle, said turret, index gear and rotatingring being integrally secured together and rotatably mounted on saidsaddle, a first fluid pressure (bydraulic) cylinder, a rack operated bya piston rod of said first fluid pressure cylinder, means to pivotallyconnect said cylinder to said saddle so as to establish or interruptdriving connection between said index gear and said rack, a second fluidpressure cylinder, a dowel pin carried by a piston rod of said secondfluid pressure cylinder and adapted to be received in a predeterminedone of said depressions to determine the position of said turret, andmeans responsive to the operation of said second fluid pressure cylinderto cause pivoted motion of said first fluid cylinder whereby toestablish or interrupt said driving connection.

This invention can be more fully understood from the following detaileddescription with reference to the accompanying drawing, in which:

FIG. 1 shows a cross-section of the essential portion of the turretindexing mechanism embodying this invention;

FIG. 2 shows a sectional view of the mechanism shown in FIG. 1 takenalong a line IIII- FIG. 3 is a fragmentary schematic sectional viewshowing the rack of the mechanism in the engaged position;

FIG. 4 is a fragmentary schematic sectional view, similar to FIG. 3, butshowing the rack in the disengaged position;

FIG. 5 is a fragmentary schematic sectional view showing directengagement of the index gear and rack; and

FIG. 6 is a view similar to FIG. 5, but showing the rack in a disengagedposition.

Referring now to the accompanying drawing, an index gear 2 and a rotaryring 3 having a plurality of equally spaced depressions or openings 3aon its periphery are integrally secured to a turret 1 which carries anumber of tools, not shown, and is rotatably mounted on a saddle 5slidably fitted on guide rails 4. The index gear 2 is coupled to a rack7a through an intermediate pinion 6. The rack 7a is connected to apiston rod 7 of a first fluid pressure cylinder 8 which is pivotallyconnected to saddle 5 by means of a pivot pin 9 so as tocause rack 7a toengage with or disengage from intermediate pinion 6. The stroke ofpiston rod 7 is limited by a pair of stops 10 and 11 which are adjustedto adjust the range of indexing of turret 1. Rotation of piston rod 7 isprevented by a key 12 received in a key slot 7b on the bottom surfacethereof. A second fluid pressure cylinder 14 is secured to saddle 5 andis provided with a piston rod 13 formed with a dowel pin 13a at itsouter end that cooperates with said depressions 3a to determine theposition of turret 1. The opposite end of the piston rod 13 extendsthrough the closed end of the cylinder and is connected one arm of acrank lever 16 pivotally con nected to saddle 5 at 15. The opposite armof crank lever 16 is connected through a lever 17 to a point of cylinder8 longitudinally spaced from its pivot pin 9.

FIG. 3 shows the indexing operation, and FIG. 4 the disengaged state ofthe gear 2 with relation to the rack 7a.

FIG. 5 shows direct engagement between the gear 2 and the rack 7a; FIG.6, the disengaged position.

In operation, when a fluid under pressure, for example, pressurized oilis introduced into a chamber 18 in the first fluid pressure cylinder 8,piston rod 7 is advanced to impart an indexing motion to turret 1through rack 7a, intermediate pinion 6 and index gear 2. Thus, turret 1completes one indexing step when the outer end of piston rod 7 engagesstop 10 whereby to bring a predetermined one of depressions 3a to aposition facing dowel pin 13a. Concurrently therewith, pressurized oilis admitted into a chamber 19 in the second fluid pressure cylinder 14to advance piston rod 13 and its dowel pin 13a into a predetermined oneof said depressions 3a to hold turret 1 in its indexed position. Thismovement of piston rod 13 causes the first fluid pressure cylinder 8 topivot around its pivot pin 9 in the clockwise direction through cranklever 16 and link 17 to disengage rack 7a from intermediate pinion 6,the arrangement being such that rack 7a disengages from intermediatepinion 6 only after dowel pin 13a has been received in one ofdepressions 3a. Piston rod 7 of the first fluid pressure cylinder 8 isretracted by admitting pressurized oil into a chamber 20 on the oppositeside while rack 7a is maintained out of engagement from intermediatepinion 6.

During the next indexing step, pressurized oil is admitted into achamber 21 in the second fluid pressure cylinder 14 to withdraw dowelpin 13a out of depression 3a and to pivot the first fluid pressurecylinder 8 in the counterclockwise direction through crank lever 16 andlink 17, thus causing rack 7a to engage intermediate pinion 6 beforedowel pin 13a is completely withdrawn from one of the depressions 3a.Finally, the mechanism is restored to the position shown in FIG. 1, andthe cycle of operation mentioned above is repeated. While, in theillustrated embodiments, rack 7a is shown as being adapted to engagewith and disengage from intermediate pinion 6, it will be obvious tothose skilled inthe art that rack 7a may directly engage with anddisengage from index gear 2. Further, means for operating the fluidpressure cylinders are not shown because they are well known in the art.

Thus, this invention provides an improved turret indexing mechanismhaving rugged construction and yet being capable of operating verysmoothly without any excessive rotation as well as impacts of the turretagainst the dowel pin.

While I have illustrated and described a specific form of mechanismembodying my invention, various other arrangements will occur to thoseskilled in the art. I do not, therefore, desire my invention to belimited to the details of construction and specific arrangementdisclosed, and I intend, by the appended claims, to cover allmodifications which fall within the spirit and scope of my invention.

What I claim is:

1. A turret indexing mechanism comprising a turret, an index gear, arotating ring having a plurality of equally spaced depressions on theperiphery thereof, a saddle, said turret, index gear and rotating ringbeing integrally secured together and rotatably mounted on said saddle,a first fluid pressure cylinder, a rack operated by a piston rod of saidfirst fluid pressure cylinder, means to pivotally connect said cylinderto said saddle so as to establish or interrupt driving connectionbetween said index gear and said rack, a second fluid pressure cylinder,a dowel pin carried by a piston rod of said second fluid pressurecylinder and adapted to be received in a predetermined one of saiddepressions to determine the position of said turret and meansresponsive to the operation of said second fluid pressure cylinder tocause pivotal motion of said first fiuid pressure cylinder whereby toestablish or interrupt said driving connection.

2. The turret indexing mechanism according to claim 1 wherein said lastmentioned means includes a motion transmitting linkage between thepiston rod of said second fluid pressure cylinder and said first fluidpressure cylinder.

3. The turret indexing mechanism according to claim 1 wherein said rackis caused to directly engage with and disengage from said index gear bythe pivotal motion of said first fluid pressure cylinder.

4. The turret indexing mechanism according to claim 1 wherein anintermediate pinion is provided between said index gear and said rack.

References Cited UNITED STATES PATENTS 1,947,348 2/ 1934 Lovejoy.

2,400,691 5/ 1946 Grad 74822 2,952,169 9/1960 Johnson 74-822 3,085,4524/ 1963 Thompson 74-822 FRED C. MATTERN, JR., Primary Examiner.

F. D. SHOEMAKER, Assistant Examiner.

